breaking news. we have new details on two of the most closely watched trials of the year. sudden holes develop in the case against former imf chief dominique strauss-kahn, with serious questions about his accuser's credibility. and, casey anthony's defense rests as a surprise witness challenges her father's testimony. we have the latest on both. mission unstoppable. it might be the craziest race on earth. one extreme challenge after another, for three days, with no sle sleep. where even the strong barely survive. and, hope on jobs. after tackling the rest of the world's problems, bill clinton has a plan to put over 100,000 americans back to work. he explains how in an exclusisi

interview, and he answers the grandkids question. >> announcer: from the grlobal sources of abc news, with terry moramoran, cynthia mcfadd and bill weir inn new york city this is "nightline," june 30th, 2011. >> good evening, i'm bill weir. and we begin tonight with breaking news, in two of the highest profile cases in the land. starting with dominique strauss-kahn, the former imf chief accused of raping a hotel maid. abc news has learned that the prosecution case is unraveling tonight after the manhattan district attorney's office discovered serious credibility issues with the alleged victim. we've confirmed a "new york times" report that authorities recorded the maid as she called a suspected drug dealer and discussed ways to profit from the charges. there are other big holes in her story that could lead to strauss-kahn's release from house arrest as early as tomorrow. and, in another twisting,

turning legal drama, the casey anthony defense opened her florida trial by claiming she didn't murder here toddler, but lied about the accidental drowning because casey had been sexually abused by her own father, george anthony. well, today the defense rested, but not before calling out george anthony once again, this time, accusing him of an affair. here's abc's john donvan, for our series "crime and punishment." >> is it your decision not to testify based upon consultation with your counsel? >> yes, , r. >> reporter: those two words today, and she would repeat them as the question was put to her more than once. >> yes, sir. >> reporter: they told us that this, after all, yes, sir, is all we're going to hear from the murder defendant, who, by the time the defense rested today, after two weeks of testimony, seemed, , her silence, to have left an awful lot unexplained. as in, why, when he daughter caylee disappeared, she, the mom, went out partying. why she blamed the disappearance

on a nanny -- >> s-e-n-a-i-d-a -- >> reporter: who does not exist. why she accused her father george of disposing of the body and then on top of that, accused him on sexually abusing her when she was a little girl. >> her father came into her room and began to touch her inappropriately. >> have you ever sexual little molested your daughter? >> no, sir. >> reporter: on top of that, her lawyer today calls a woman named krystal holloway, claiming to have had an affair with george, her father, who is married. >> was this an intimate relationship? >> yes. >> reporter: and to put yourself in george anthony's place, it's awful. ananwe saw that on the stand yesterday when, yet one more time, they took him through the events of the day that he learned his granddaughter's body had been found. >> up to that moment, had you held out the hope that caylee

would be found alive? >> absolutely. every day from july 15th until the day we were told it was caylee -- >> reporter: and all during these minutes, on the face of his daughter? nothing. which is such a dramatic contrast to the father-daughter story that was told earlier in this trial the jailhouse scenes that the prosecution built into its case. except for the glass that separated them, they were obviously shoulder to shoulder at that point. >> you are the best father and by far the best grandfather that i have ever met. >> reporter: and he clearly loved his granddaughter the day she was born, with no father present, george and his wife cindy were there at the hospital and they loved her. swam with her in the pool, as seen in video license bid abc news. and during those days after caylee disappeared, george was out front in the searching. and in keeping the public on

alert. all of which casey saw, before she was arrested and charged with murder. but once the trial started back in may, he became a father in a terrible position. one of the prosecution's best wit 'ns, as they sought the death penalty for a daughter he does not want to die. and whose side was de%ing him as a villain. they said he molested his daughter and doing so, turned her into a liar. they say he talked her into covering up the little girl's death. he had to witnene hearing h h son being accused of also molesting casey. but he held together until the emotional crumbling that we've seen this week. >> do o u need a break, mr. anthony? >> no, sir. i need to get through this. i need to have something inside of me get through this. >> reporter: and his admission that he had bought a gun at one point and checked into a motel and had written out a suicide note. >> late january of 2009, you attempted to commit suicide. did you, sir? >> yes, sir, i did.

>> reporter: today, there were no tears. as he heard krystal holloway say not only that he had an affair with her but he told her things about caylee's dispeernts. >> he had said it was an accident that snowballed out of control. >> reporter: a story that began to fall apart under cross examination, along with holloway's credibility. >> you had no choice but to tell >> yes, sir, i did lie.. >> reporter: it's the sense of the courtroom that george anthony has successfully fended off these accusations of adultery and sexual abuse. >> i think the defense would have been far better off from the beginning, simply saying this was an accident. rather than pointing the finger at george anthony, in the way that they did, and now coming up as short as they did. >> reporter: but the truth is, his daughter's lawyers needed those charges to stick because in terms of a defense, making george a bad father and husband, it was all they had. >> your honor, the defense rests. >> reporter: i'm john donvan for "nightline" in washington.

>> our thanks to john for that. and just ahead, we check out one of the most creatively sadistic endurance races on the planet. host: could switching to geico really save you 15% or more on car insurance?

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[ male announcer ] nature valley sweet & salty nut bars... they're made from whole roasted nuts and dipped in creamy peanut butter... ♪ ...making your craving for a sweet & salty bar... ♪ ..rresistible. by nature valley. ♪ >> announcer: "nightline" continues from new york city with bill weir. >> they say there are only three animals that will run themselves to death. dogs, horses and humans. and while no one dies in the contest of endurance you're about to see, thankfully, it does raise questions about the human capacity for self-inflicted physical punishment and relative sanity. here's abc's john berman, deking deep at the spartan death race. >> reporter: carrying a tree

stump up a mountain? that's tough. crawling through a drainage pipe? that's tough. hiking miles through a frigid ver in the middle of the night? that's tough. but doing it back to back to back over three days with no sleep? that's freaking insane. should i worry about you? >> no, i'm all right. >> reporter: 150 racers in what might be the most challenging, not to mention diabolical, race on the planet. the spartan death race, in pittsfield, vermont. founded six years ago by joe and andy, for one reason. >> the goal here is not to pat people on the back and not to give them water, not to tell them how great they are that's every other race. the goal here is to exploit their weakness and break them. >> reporter: the racers have no idea what's in store for them when they arrive.

how many tasks or when the race is over. death racers anthony and reed, both in the their 40s, are here for the third straight year. the last two years, they quit mid-race. still -- >> i enjoy the challenge. >> i feel most alive when i'm pushing myself. >> reporter: like most men and women here, and yes, there are women, these guys are fit. reed is a firefighter and former marine, and anthony, who owns a restaurant, used to lead wilderness expeditions. day one. the race begins at 6:00 p.m. the first challenge? stand in a circle and pick up these rather large rocks more than 1,000 times. how you feeling? >> feel like you can't think about it, you know what i'm saying? you got to worry about the task in front of you and then worry about the pain later. >> reporter: they do this for five straight hours. and just w wn their bodies are dripping wet, with muscles

burning at 1:00 in the morning, they take to the river for a hike. 45 degree water in pitch black, wearing a huge backpack. we see reed. you're still smiling. >> i am. i think it's frozen. >> reporter: 4:30 a.m. after the river is a pond. how is the water? >> cold [ bleep ]. cold as jesus, man. freezing in there. >> reporter: then a walk in a circle, carrying the candle without the candle burning out. they have to do the pond-candle loop seven times. and it's just the e ginning. daylight brings more drama. lug a tree stump up a hill, memorize a bible verse and recite it out loud. >> be watchful, stand firm in the face, act like men, be strong. >> there you go. >> nice job! >> reporter: it's not easy. after 18 hours, the mind is clearly starting to go. is it hard for you to string together sentences? i was really -- i -- i was --

um -- >> reporter: a fresh change of clothes can help some, but anthony has a long way to go. a hike that will take hours, with a 36-inch treetump that he had to cut on his back. god speed. >> great. >> reporter: a hike that begins to claim dozens and dozens of even the toughest. >> i think i got an infection. look at that. >> i'm done. >> reporter: these people are legit psychos. >> reporter: but 24 hours in, no sleep and reed is still working and still hiking. it's pouring rain. walking through the mud. at what point does this become not cool but just stupid? >> well -- now it's just auto pilot. you made such an investment at this point. you have to keep trudging along. >> reporter: lest you think this is easy, i tried on his% with

that stump inside. so, you just walked up a mountain for six hours with this thing on your back. >> yeah. >> reporter: he trudges on. but we learn his friend anthony does not. >> see ya. >> reporter:r:5 1/2 hours into the race, he gives up. >> pissed off that my body detraded me a little bit. and, you know, pissed off at myself for having to utter those words, you know, "i'm done." which gets translated into you quit. so, that sucks. >> reporter: how about a hug? >> i'll take it. >> reporter: but reed is still out there. at 7:00 a.m. day three, awake, his body chopping wood. his mind -- >> i was thinking last night, the white water was white sheets flapping around in the woods. definitely tired. but trucking along.

>> reporter: 45 hours into the race, all the racers are summoned to a 3:00 p.m. meeting at church. the race is over. anyone still running declared a finisher. 35 racers madad it. reed is one of them. >> this is my trophy for finishing. coming to church and hearing those words that it was over, it was miraculous. >> reporter: miraculous, amazing, possibly foolhardy. is this something humans are meant to do? maybe not. is it something we can do? barely. i'm john berman for "nightline" barely. i'm john berman for "nightline" in pittsfield, vermont.loans, e to go the extra mile for our clients. with the wassman family, it was 2,500 extra miles. we're the wassman family from skagway, alaska. livin' so far out and not havin' a bank within 90 miles... i was runnin' into dead ends. happened to come across quicken loans online. [ chris ] walked over to the computer... i was able to see all the paperwork. while i was on the phone, i was able to go through the checklist. [ kathy ] they were quick and efficient.

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figures, but there are millilis more out there looking for work. and among those trying to do something about them is the president of perpetual motion. bill clinton. who sat down with abc's chief white house correspondent jake tapper for tonight's "nightline" interview. >> reporter: today in chicago, the man who oversaw the best economy in recent american history took matters into his own hands. concluding the first clinton global initiative to focus on creating j js in the u.s., bill clinton today announced pledges to help create more than 100,000 american jobs and train more than 300,000 american workers. what ideas are you hearing here at this conference that president obama and speaker boehner need to hear? >> well, first of all, there does seem to be a real feeling here that we need to find economic always to increase our

investment and infrastructure and in clean energy. and there was a great idea here today, discussi ined in our fir meeting about what to do about the so-called skills gap. there are 3 million posted job openings today. those jobs are being filled at only half the pace they were filled in previous recessions. >> reporter: at the same time unemployment is 9%. >> you got it. so, just think about it. we had 3 million people more working, unemployment would be more than two points lower than it is. and america would be in a very different place psychologically. >> reporter: and then, perhaps not surprisingly, the man who tried and failed to change health care almost 20 years ago -- >> our health care is too uncertain and too expensive. it has too much fraud and too much greed. >> reporter: got, well, passionate, or angry. depending on your point of view. >> so, what do people who attack president obamama and the healt

care law advocate can best be seen in 2009. there was no obama care. the economy was in the total tank. the worst of the recession. so, what happened? insurance company profits went up 26%, 5 million people lost their health insurance, their private health insusunce. that is the system advocated by the people who are against obama care. these people are defending system that is bankrupting the american compaeconomy, that is keeping people are getting jobs, that is keeping the american people from getting pay inkreenss because we have to gobble up a trillion dollars a year to a health care system in ways that are unrelated to our health. that's my response to that. otherwise, didn't have strong feelings about this issue. >> reporter: another issue where he has strong feelings -- same sex marriage, just legalized in his adopted home state of new york. i know this is an issue that you've changed your mind on. >> i have, yeah.

>> reporter: do you agree w wh progressives in yourarty who say president obama is missing an opportunity to lead on this issue? or do you think what he's doing is politically wise? >> this is not likee a lot of other civil rights. this is really one where i think most people are clawing their way through a thicket of complex issues. i think the president has been quite good on gay rights. i'm glad that we got the don't ask, don't tell, thing behind us. and i ththk the country's moving in the right direction. >> reporter: and speaking of marriage, his daughter chelsea wed one year ago next month. is he eager for grandkinds? >> less i say about it, the better. >> reporter: don't want to jinx it? >> don't want to jinx it and i don't want to interfere with it. i just one day hope i get to be a crotchety old grandfather. but that's not up to me. >> reporter: for "nightline," i'm jake tapper in chicago.